In the case of recording a video signal with wideband on a recording medium such as a magnetic tape, an input video signal (FIG. 23a) is sometimes arranged to undergo double time base extension by the use of time base conversion means, and are divided into two channels to be recorded or reproduced. In conventional video signal recording-reproduction devices, every odd numbered 1H (horizontal scanning period) of those divided video signals (FIG. 23a) is made to form a recording signal (FIG. 23b) for channel 1 (CH1) while every even numbered 1H is made to form a record signal (FIG. 23c) for channel 2 (CH2), and thereby those two signals are recorded with the same phase. On the other hand, in reproduction, the divided record signals of two channels (FIGS. 23b,c) are converted into the same signal as the input video signal before being divided (FIG. 23a), by conducting time base compression.
However, the conventional video signal recording-reproduction devices present a problem that a complicated circuit configuration is needed for converting the divided recording signals of two channels (FIGS. 23b,c) into the input video signal (FIG. 23a) before being divided in reproduction.
More specifically, when the divided recording signals (FIGS. 23b,c) undergo time base compression, sync separated signals (FIGS. 23d,e) corresponding to a horizontal synchronizing signal of the input video signal (FIG. 23a) are used as reference signals. In this case, since these separated sync signals (FIGS. 23d,e) are formed by reproducing the recording signals (FIGS. 23b,c) recorded with the same phase, they also have the same phase. Accordingly, when the separated sync signals (FIGS. 23d,e) are used as reference signals, a frequency doubler is necessary in order to conform the phase to that of the horizontal synchronizing signal which the input video signal (FIG. 23a) possessed, thereby causing a complicated circuit configuration.